WRITE_SOB_FRACTION:
  PUSH(FP);
  MOV(FP, SP);
  
  //writing numerator:
  MOV(R0, FPARG(0));		// R0 = pointer to sob fraction
  MOV(R0, INDD(R0, 1));		// R0 = R0[1] = numerator
  PUSH(R0);
  CALL(WRITE_INTEGER);
  DROP(1);
  //writing '/'
  PUSH(IMM('/'));
  CALL(PUTCHAR);
  DROP(1);
  //writing denumerator:
  MOV(R0, FPARG(0));		// R0 = pointer to sob fraction
  MOV(R0, INDD(R0, 2));		// R0 = R0[2] = denumerator
  PUSH(R0);
  CALL(WRITE_INTEGER);
  DROP(1);
  
  POP(FP);
  RETURN;